Locomotive boiler



April 9, 1929. w, BRUCE 1,708,255

LOCOMOTIVE BOILER Filed Jan. 11, 1927 2 Sheets-Sheet l WITN v 5E (3 INV WWW April 9, 1929.

A. w. BRUCE nocomohim' 39mm ts-shoet Fwd-Jan. 11, 1927 WIT 5 E5 AZ z? Patented Apr. 9, 1929.

UNITED STATES ALFRED W. BRUCE, OF NEW YORK, N. Y.

LOGQMOTIVE BOILER.

Application filed January 11, 1927. Serial No. 160,330.

My invention relates to boilers of the 10- comotive type, and of the class thereof in which the sides of the fire box and combustion chamber are formed of a plurality of water tubes, an instance of which is exempliiied'in the patent of J. M. McClellon, No. 1,580,063, April 6, 1926. My present invention is particularly directed to the adaptation of a boiler of the type specified, for operation under comparatively high steam pressure, and to effecting a reduction of the weight and dimensions of the boiler to a substantial extent. Acharacteristie feature of my invention is the application of separate circulation systems for the the box and for the barrel of the boiler.

The improvement claimed is hereinafter fully set forth:

In the accompanying drawings; Figure 1 is a vertical longitudinal central section through a boiler embodying my invention; Fig. 2, a half plan view thereof; Fig. 3, a vertical transverse section, the right hand half being taken on the line 111, III of Fig. 1, and the left half on, the line III, III thereof; Fig. 4, a similar section, the right hand half being taken on the line TV, IV of Fig. 1, and the left hand half on the line IV, IV thereof; and Fig. 5, a similar section on the line V, V of Fig. 1.

In the practice of my invention, referring descriptively 'to the specific embodiment thereof which is herein exemplified, the improved locomotive boiler thereof comprises three-main sections; the fire box, A, the boiler barrel, B, through which extends a plurality of lire tubes, 3 and the smoke box, 0, and a combustion chamber, D, is located in the forward portion 'of the fire box. The mud ring, 2, of the fire box, is hollow, and forms the bottom support of a plurality of water tubes, 3, which are set closely together, forming the side walls of the fire box, and are connected, at their upper ends, with a drum, 4, which extends horizontally and for wardly over the barrel, B, in this instance to a front header, 12, with which it communicates, which header communicates with the barrel, B. The mud ring, 2, at its rear end, supports, and communicates with, the back head, 5. Arch tubes, 6, which support a lire brick arch, 7 are connected to the front of the mud ring, and extend upwardly and rearwardly to the back head, 5. The upper surface of the grate, 8, lies approximately in the plane of the top of the mud ring. The forward limb of the mud ring is apertured for communication with a feed water connection, 10, leading into the barrel, B, to the forward portion of which, water is supplied through a feed pipe (not shown) provided with a check valve, in the ordinary manner.

The water tubes, 3", of the combustion chamber, D, form continuous walls with the fire box water tubes, 3, and conform in curvature therewith, above the axial line of the barrel, below which they are curved on are struck substantially radially from said axial line. The water tubes, 3 and 3, are connected, at their tops, to the drum, 4, and, at their bottoms, to the mud ring, 2, and to a feed water member, 11 respectively. The member, 11, extends forwardly to a connecti on with the barrel, B, and provides a water passage from said barrel to the bottoms of the combustion chamber water tubes, 3,

while a connection, 10, independently supplies water from the barrel, B, to the mud ring, 2, and, through the mud ring, to the fire box side water tubes, 3, the arch tubes, 6, and the back head, 5.

Headers, 12 and 13, are located at the front and rear ends, respectively, of the barrel, B. The drum, 4, extends through both headers, but is in communication with the front header, 12, only, through ports, 1.4. Two smaller drums, 15, 15, are disposed on the opposite sides of the drum, 4, exterior to the barrel, said smaller drums extending from the header, 12, to the header, 13, and being in communication with the barrel through said headers.

A suitable throttle valve, 16, is located adjacent to the front of the drum, 4, and controls communication between said drum and steam supply pipes, 17, leading therefrom to a super-heater, 18, or to the valve chests of a locomotive, as the case may be. If desired, a vertical longitudinal bafile plate, 19, may be fitted in the portion of the drum, 4, that ex tends through the fire box and combustion chamber, to prevent interference of the currents of water rising from the tubes on opposite sides thereof.

In the operation of a boiler of the construction hereinbefore specified, steam generated in the back head, 5, and side water tubes, 3 and 3, flows forwardly through the drum, 4. Steam generated in the barrel, B, rises through the header, 13, into the smaller drums, 15,'fiows forwardly through them into the header, 12, and thence enters the forward end of the drum, 4, through tliports, 14. There is thus a flow of s eain forwardly from the water tube walls of the lire box, through the drum, 4, to the throttle valve, 16, and a flow of steam from the bar rel, rearwardly through the drum, l, to the throttle valve. traverses past the throttle valve, through the pipes, 17, to the superheater, 18, or directly to the valve chests of the locomotive. There is likewise an independent circulation of steam vgenerated in the barrel from the rear to the forward ends thereof, through the lateral drums, 15,15. v

A wrapper sheet, 20, which encircles and housest'he fire box and the combustion chamber is se'c'uredto the header, 13, the back head, 5, and the mud ring, 2, said wrapper performing, primarily the function of a rigid conn'rcting member for the fire box and 'jboilerfbarrel, and. secondarily, that of a closure or housing for the top of the fire box, to prevent the escape of gases of combustion tl ierefrom. Suitable lagging or insulating material, 21, is applied, between the outsioes of the water tubes, Band 3", and the wrap- .per sheet. I

7' Boilers embodying. my invention present the advantage of decreasing the diameter of theboiler barrel, B, with a resultant reduc tion' in weight; the eliinination of structural -Cllfil0llll316$ and increase in the factor of safety; and the provision .of separate circu- .la-tion systems for the fire box and the boiler barrel, thereby increasing the rapidity of circul'ation and mechanically controlling the circulation to prevent interference ot the water circuits, all of which features effect a substantial increase in ei'liciency. The boiler ,is of a form adapted for carrying the highest steam pressures now utilized in service or contemplated in locomotive operation.

. I claim as my invention and desire to secure by Letters Patent:

1.. In a boiler of the locomotive type, the combination of a fire box, the sides of .w-laich are formed of water tubes; a barrel,

extending forwardlyfrom the forward end of the the box; a druin,-extending forwardly from the rear end of the fire box and cominunicating with the side water tubes thei'eof; ,means, connecting the interior of the forward end of the drum with the interior ofthe forward end of the barrel; and supplem entalmeans, establ shing circulation be- Steam from both sources,

tween the rear and the the barrel. v

2. In a boiler of the locomotive type, the combination of a fire box, the sides of which are formed of water tubes; a barrel, extendingforwardly from the forward end of the fire box; a drum, extending forwardly from therear end of the fire box and comforward portions of in'uni'cating With the side water tubes thereof and, with the barrel; headers, located at the opposite ends of the barrel; and supplemental means, establishing steam circulation, through said headers between the rear and the forward portions of the barrel. 7

3. in a boiler: of the locomotive type, the combination of a fire box,the sides of which are formed of water tubes; a barrel, extending forwardly from the forwardend of the fire box; a drum, extending forwardly from the rear end of 'the'fire box and communicating with the side water tubes thereof and with the barrel; headers, communieating with the opposite ends of thebarrel;

and lateral drums connected at their ends to the'interior of's'aid headers. ,7

4. In a boiler of the locomotive type, the combination of a fire box, the sides of which are formed of water tubes; a barrel; headers, disposed at the ends of "the barrel, and in communication therewith at their lower portions; a drum, extending forwardly from {the rear'end of the fire box, and in corninunication with said water tubes and with one of said headers; a water circuit, comprising said headers; water connections between the upper portions of the headers, and "said barrel, whereby steam generated in such circuit is supplied to the drum; and a second water circuit, comprising feed water connections, delivering water to the side water tubes from the barrel, said'drum and said header establishing communication betw-veen said dependently from the barrel to different 10- cations in the side water tubes ALFRED W. isnnon 

